The objectives of this study were to examine the excretion of urinary DEHP metabolites and to assess human health risk from DEHP exposure. The exposure levels of DEHP metabolites increased in the
order of control female(GM 62.9 μg/g creatinine), mothers(GM 68.7 μg/g creatinine) and children(GM 246.1 μg/g creatinine). Spearman’s rank correlation analysis revealed significant correlations(p-value ≤
0.01) in the MEHP concentrations between the mothers and children.
Relative metabolic rate(RMR) were calculated to examine the difference in DEHP exposure levels to the primary and secondary metabolites. MEHP hydroxylation to MEHHP(1st step, RMR1) followed by
MEHHP oxidation to MEOHP(2nd step, RMR2). The RMR1 and RMR2 of children, mothers and control female were very significant to each other (both p-values ≤ 0.0005) and children had the highest
value of RMR1 and RMRt. Children group had particularly faster relative metabolic rate in the first step (MEHP hydroxylation to MEHHP) of DEHP metabolism than mothers and control female group.
RMRt has the potential as a biomarker for assessing exposure of DEHP by age. Combined with sample volunteer’s health information, the above study would be a useful source that can be referred to make
an assessment of human metabolic system.